The present invention is generally directed to mobile communications, and more particularly to increasing the number of available geographical addresses in regions of the Earth that are closer to the equator than the South or North poles.
When geographical addresses are used in a network to identify and route communications, a unique geographical address for each device typically includes each device""s latitude and longitude coordinates in a discrete number of bits. However, since longitudinal lines are closer to each other the nearer they get to the North or South poles of the Earth, the number of available geographical addresses based on the latitude and longitude coordinates of the physical locations of devices are more concentrated in regions nearer to the North and South poles. As a result, fewer geographical addresses are available in the more highly populated regions of the Earth, which tend to be closer to the equator than near the North or South poles.
However, the number of bits for geographical addresses can be increased to include more bits for resolving latitude and longitude coordinates within each region. The higher resolution of the larger geographical addresses makes more addresses available for every region on the Earth, including those regions closer to the equator. However, increasing the total number of larger geographical addresses that are available in every region on the Earth does not correct the problem of having a higher concentration of these addresses in regions nearer to the North and South poles.
By increasing the size (number of bits) of the geographical address, a greater amount of network resources is consumed when the addresses are employed in the packets sent over the network. In wireless networks, where every packet is at least partially routed based on the location of each packet""s destination, typically at least one geographical address is present in every packet header. Minimizing the size of the geographical address and therefore also the sizes of the packet headers aims in maximizing the efficiency by saving the network capacity for the actual data to be transferred. Therefore, it would be useful to increase the number of geographical addresses for regions that are closer to the equator of the Earth than the North or South poles, and in doing so, not significantly increase the number of bits in the geographical addresses. Also, in some cases the length of the address field may be already fixed and therefore increasing the number of addresses for certain areas is not possible by increasing the total number of bits in the addresses.
The present invention is directed at addressing the above-mentioned shortcomings, disadvantages and problems, and will be understood by reading and studying the following specification.
According to one aspect of the invention, a method is provided for generating geographical addresses for mobile devices disposed on the surface of the Earth. At least a latitude coordinate and a longitude coordinate for a geographical position of a mobile device is determined. Also, another coordinate that corresponds to the latitude coordinate of the mobile device is determined. The determination of the other coordinate increases the number of latitude coordinates that are determinable for the mobile device in at least one region of the Earth. A geographical address for the mobile device is generated that includes the other coordinate and the longitude coordinate. By including the determined other coordinate and the longitude coordinate in each geographical address, substantially more geographical addresses can be generated for each mobile device disposed in at least one region of the Earth than a different geographical address of relatively the same size that includes the latitude coordinate and the longitude coordinate of the mobile device.
In accordance with another aspect of the invention, an altitude coordinate is determined for the geographical position of the mobile device. The altitude coordinate is also used to generate the geographical address of the mobile device. Additionally, the determination of at least the latitude coordinate and the longitude coordinate employs at least one of AGPS, GPS and triangulation.
In accordance with yet another aspect of the invention, the other coordinate is determined from the result of performing a sine function on the latitude coordinate. Additionally, the other coordinate can be determined with at least one equation, including latitudebits=(2xxe2x88x921)/sin(latitude). Where x represents the number of bits reserved for the determined sine of the latitude coordinate in the geographical address, latitudebits represents the other coordinate and latitude represents the latitude coordinate.
In accordance with still another aspect of the invention, the determination of the other coordinate includes accessing a table of other coordinates that are predetermined and correspond to latitude coordinates. Each predetermined other coordinate corresponds to each longitude coordinate that is determinable in at least one region of the Earth. Additionally, employing the other coordinate in the geographical address causes relatively more geographical addresses to be generated for each mobile device disposed in at least one region located nearer to the equator of the Earth than another region located closer to the South Pole or yet another region located closer to the North Pole.
In accordance with the invention, the geographical address for the mobile device and another geographical address for another mobile device is employed to establish communication and enable the routing of packets between the location of the mobile device and another location of the other mobile device over a network. Also, each mobile device on the network can forward a request for communication between the mobile device and the other mobile device along a path that includes at least one other mobile device on the network. Additionally, at least one geographical address of at least one other mobile device is employed to determine the path between the mobile device and the other mobile device. Furthermore, communication is established between the mobile device and the other mobile device by at least one other mobile device operating as a router disposed on the path between the mobile device and the other mobile device.
In accordance with the invention, geographical addresses of each mobile device are stored in a data store. The data store may be disposed in at least one mobile device. Also, the data store may be disposed in at least one server accessible through a base station in communication with at least one mobile device on the network.
According to other embodiments of the invention, a system may be provided for generating geographical addresses for mobile devices disposed on the surface of the Earth in substantially the same manner as the method discussed both above and below.